For the first half of my career, I was an ‘artefact researcher’. It is natural therefore that my archaeological thrillers contain plenty of objects. Objects can be dated, as can particular social habits and organisations, so we can quickly spot a piece of period fiction without being told it was set in the past. Fairly soon afterwards we start homing in on the date. A single fact the hero carries a revolver provides a terminus post quem, as archaeologists say – the date after which the story must be set. The clattering of his secretary’s typewriter provides a terminus ante quem – less reliably a date before the novel is likely to be set. The association of the two suggests middle-twentieth century.

I read Peter Robinson’s Caedmon’s Song recently and within a few pages got the uncanny feeling it was set in the past. Checking the publication date of 1990 provided the answer – it was simply a 26-year old book. The author even discusses this in his afternote to the paperback edition. ‘Contemporary’ novels do not remain contemporary for very long. Charles Dickens and Jane Austen were once contemporary novelists

My first novel Darkness Rises was set nominally in 1989, the year of the Green Party revival, although my agent advised me to omit specific contemporary events to prevent the book dating. I wrote it during 1992, inspired by my own experiences in the late eighties. So, my hero Jeffrey Flint uses a fax machine for the first time. His sidekick Tyrone is experimenting with computer databases, but Flint is far from convinced. My old hippie hero does not drive, has no phone at home and when there is a stake-out later in the book, has to borrow some walkie-talkies (which fail to work). My archaeologists use the (then) cutting-edge techniques of pollen analysis, land-snail counting and DNA fingerprinting. A lead suspect has not heard of any of these new techniques “They sound tedious,” he sneers.

By Byron’s Shadow, the ‘present’ has advanced to the mid-nineties, with flashbacks to the early eighties. Vikki the reporter now has a mobile phone, which Flint deplores. When faking documents, he has to use mapping pens and Letraset (remember Letraset?). The plot hinges around an archaeological survey, for which I intended to employ a device called a resistivity meter. This was becoming old hat by draft 2, as my own excavation unit in York had begun early experiments with ground-piercing radar. This then became the novel tool introduced by a helpful American academic: the radar was on a sledge, linked to a bulky computer. As I wrote and re-wrote, this technology moved from being theoretical to practical. It is now standard – you can see it on Time Team most weeks, but the modern machine is man-portable with global positioning and the bulky computer is now a laptop, soon to become a tablet.

Flint has reluctantly bought a van by Shadesmoor. Tyrone now has a mobile phone and flaunts his new laptop computer. The old ‘dumpy’ surveying device has been replaced by the laser-guided EDM and inevitable computer link. The University has dumped its old typewriters so Flint learns to use a PC, but the fact that the University sells off redundant machines provides a major red herring. In a few years, people might ask “what’s a typewriter?”

Artefacts abound in Lady in the Lake, from ancient swords to a decommissioned bren gun and a decrepit Citroen 2CV. The book begins with our hero watching the movie Excalibur on video. How long now before VCR machines are extinct, and readers of my backlist are puzzled by the reference? The ‘new’ technology included video discs, which are already obsolete. Archaeology moved into the mainstream during the 1990’s, and the book reflects the new commercialisation with A/V presentations and press conferences. Academic conferences are still using slide projectors and overhead projector screens however, which Powerpoint has long since condemned to the spoil-heap of history. There is a foretaste of the wave of popular history programmes that started with Time Team and now infest satellite TV, but I did not foresee the incredible 3D graphic reconstructions of ancient sites and objects now possible.

With my fifth novel and a new millennium, Flint’s 1970’s value set was increasingly out of place, so the lead role was taken by Maddy Crowe, lady illustrator and ancient fashion expert. She lives with her mobile phone, lugs around a laptop with graphics package and drives a trendy small SUV. All this high-tech gear leads the writer into new territory. Whereas Flint had to hunt down his witnesses in person (sometimes on his pushbike) Maddy simply sends an email or dials them up on her mobile. Where Flint needed to conduct laborious research in libraries, Maddy can quickly trawl the internet. Her fake documents can be knocked up in a couple of minutes on a PC. If Flint had a mobile, or the internet, half the peril of his earlier adventures would have been dissipated in moments.

Almost everyone indeed has a mobile in When the Dust Settles. This invention could rob the thriller of peril. Being stalked? Ring the cops. Lost your sidekick in the fog? Ring his mobile. Trapped in the burning building? Same. The writer must bend over backwards to get rid of those plot-spoiling phones by convenient signal black-spots, dead batteries, sly thefts or diehard old hippies who refuse to own one. Moving on to today (2016), the police are incredibly sophisticated, pushing the lone cop cracking a murder into the realm of fantasy without a good deal of special pleading.

Maddy’s ‘hairdresser’s 4×4’ may become as sure a marker for the ‘noughties’ as the Mini was for the ‘sixties’. Her mobile phone is already outdated by iphones, bluetooth technology and Borg-like ear attachments. Even the hardware used so prominently by Lisbeth Salander in the recent Girl… series is already dated. Flint’s beard, uncannily, is back in fashion. Ultimately, perhaps we are all writing period fiction.